It is yellow needle-like crystalline powder. It has good thermal stability with the decomposition temperature being 314 °C. It can improve the light-tolerance property of food pigment for preventing the change of the flavor of food. Its color will change in case of metal ion. It is slightly soluble in water, soluble in an alkaline aqueous solution. Quercetin and its derivatives is a kind of flavonoid compound which are widely present in a variety of vegetables and fruits such as onions, sea buckthorn, hawthorn, locust, tea. It has effects of anti-free radical, anti-oxidation, anti-bacterial, anti-viral as well as anti-allergic. For application in lard, its various antioxidant indicators are similar with that of BHA or PG.
Quercetin it has application of being used as a metal chelate or being the receptor of the free groups produced during the oxidation process of grease. In this case, it can be used as the antioxidants of ascorbic acid or grease. It also has a diuretic effect.